1. Field of Invention
The present invention relates to an image display device and a projector. More specifically, the invention relates to an image display device using a tilt-mirror device and a technique suitable for a color-display projector using a solid light-emitting element, such as an LED element as a light source.
2. Description of Related Art
According to advances in the increase in brightness and fineness of projected images, an image display device having a tilt-mirror device has been used as a light-modulation device. When a white light source, such as a metal halide lamp, is used as a light source, color splitting is performed in time serial order using a color wheel comprising combined three-color filer for red light (referred to below as an R ray), green light (referred to below as a G ray), and blue light (referred to below as a B ray). Then, within one frame of images, the tilt-mirror device is illuminated with respective R, G, and B rays. Thereby, a full-color image is projected on a screen.
If the power of the white light source, such as the metal halide lamp, is increased for increasing brightness of displayed images, the light source increases in size, and the amount of produced heat also increases by virtue of the power up. Therefore, instead of the white light source, a light-emitting element, such as a light emitting diode (LED) or a semiconductor laser diode (LD), may be used as a light source. For example, the development of the LED arises recently, and in particular the practical application of a blue LED with high accuracy has made a progress. In this case, within one frame of images, light-emitting elements for R, G, and B rays are sequentially turned on in turn so as to illuminate the tilt-mirror device. Thereby, a full-color image is projected on a screen.